Final answer:
Welded pipe fittings are used to connect pipe sections and must be welded using heat from gas, electricity, or laser. Different materials like copper are used for their malleable and ductile properties, and compatibility is key to avoid corrosion at joints.
Step-by-step explanation:
Welded pipe fittings are components used to join sections of pipe together in piping systems. These fittings come in various shapes, sizes, and materials, and are created using welding processes that involve the application of heat and pressure to fuse the fittings to pipes, often enhanced with solder. During welding, different sources of heat may be employed, such as gas, electricity, or laser. Welded fittings are critical in numerous applications, including water pipes, gas and fire pipelines, as well as electrical and communications conduit. They must be capable of withstanding high temperatures and pressures, and often, materials like copper are chosen for their malleable and ductile properties. However, consideration must be given to the compatibility of materials to prevent issues such as corrosion. For example, joints between iron (Fe) and lead (Pb) or copper (Cu) and iron can lead to corrosion due to electrochemical reactions at the junction.